Adjustable seats and components therefor &#34;A&#34; version

ABSTRACT

This invention relates to adjustable seats and components therefor including mechanisms for assisting in their adjustability and a hand-operated lever employed for both adjusting the inclination and height of the seat cushion above the base of the seat and positioning and moving the seat longitudinally.

FIELD OF INVENTION

This invention relates to adjustable seats and components thereforincluding, mechanisms for assisting in their adjustability and, ahand-operated lever employed for both adjusting the inclination andheight of the seat cushion above the base of the seat and positioningand moving the seat longitudinally.

BACKGROUND OF THE INVENTION

Seats including mechanisms for providing adjustment of the inclinationof the seat cushion and the vertical position of the seat cushion abovethe base of the seat are known in the art. In this regard see U.S. Pat.Nos. 2,609,029; 2,792,873; 2,795,267; 2,942,647; 3,147,945; 3,165,351;3,552,707; 3,662,984; 3,692,271; 4,190,225; 4,222,543; and 4,247,071.

Some of these patents also teach hand-operated levers and associatedmechanisms and components employed for positioning and moving the seatlongitudinally. See U.S. Pat. Nos. 2,792,873; 2,795,267; 3,147,945; and3,662,984. See also U.S. Pat. No. 3,659,895 which teaches an actuatinghandle and associated mechanism and components which are used to actuaterotational movement of a seat assembly about a vertical axis andlongitudinal movement of the seat both forward and backwards withrespect to the vheicle.

However, each proposal taught suffers some disadvantage, for example,sloppiness, noise during operation, cost of manufacture and complexityof assembly and operation. By way of example, the structure taught byU.S. Pat. No. 4,190,255 is noisy to operate, sloppy and expensive tomanufacture, being more suitable for use in heavy-duty off-roadequipment where there is not concern for "seat chucking", sloppiness andnoise of operation.

It is therefore an object of this invention to provide an improved seatassembly and mechanisms therefor for use to adjust the position of theseat cushion of a seat providing improved adjustability of theinclination of the seat cushion, and the vertical position of the seatcushion above the seat base of the seat. In this regard, the seat ismore easily adjusted without noise, sloppiness and complexity ofassembly and operation, whether the rear of the seat cushion ispositioned higher or lower than the front of the seat cushion or thevertical height of the seat is raised or lowered.

It is a further object of this invention to provide an improvedhand-operated lever and associated mechanism and components thereforwhich are used to actuate longitudinal movement of the seat and toadjust the inclination of the seat cushion (to position the rear of theseat cushion higher or lower than the front of the seat cushion) and thevertical position of the seat cushion above the base.

Further and other objects of the invention will be realized by thoseskilled in the art from the following summary of the invention anddetailed description of an embodiment thereof.

SUMMARY OF THE INVENTION

According to one aspect of the invention, a seat adjustment assembly isprovided for adjusting the inclination and vertical position of a seatcushion of a seat above the base of the seat, the seat assemblycomprising:

(a) a base;

(b) a seat cushion supported in spaced relation above the base;

(c) a support for carrying the cushion in spaced relation above the baseand being secured thereto, the support carrying:

(i) a cam assembly disposed proximate the center thereof and carryingopposed peripheral circular (convex) portions, each opposed peripheralcircular portion rotatable about the centre of such circular portion andanother portion adjacent each circular portion the outer surfaces ofwhich other portions being closer to one another than the circularportions are close to one another (for example, recesses, indentedportions, indentations);

(ii) means to permit the rotation of at least one circular cam portionat a time;

(iii) a pair of pawls on either side of the cam assembly, each pawlbeing secured for pivotal movement and having its end closest the camassembly carrying a circular recess corresponding in shape to thecircular cam portion for normally being engaged therewith wherebyrotation of at least one of the circular portions about its center (asfor example, by pivoting of the one part of the cam assembly carryingthe circular portion to be displaced or rotation of the cam assembly ora portion thereof) permits the end of the pawl carrying the recess tofollow the outer surface of the cam assembly from the circular portionto the portion adjacent each circular portion, thereby releasing theassociated pawl permitting the seat to be adjusted and means to causethe pawls to follow the outer surface configuration of the cam assemblyand means to return the cam assembly and pawls to their normal position.

The pawls may in turn be pivotably removably secured at their other endsto ratchets, one of which is released when one of the pawls is releasedthereby permitting adjustment of the height or inclination of the seat.

Therefore displacement of one of the circular portions of the campermits adjustment of the height of one portion of the seat. At the sametime at least one portion of the other circular portion remains in thecircular recess of the other pawl holding it in its normal position.

According to another aspect of the invention, a seat adjustment assemblyis provided for adjusting the inclination and vertical position of aseat cushion of seat above the base of a seat, the seat assemblycomprising:

(a) a base;

(b) a seat cushion supported in spaced relation above the base;

(c) a support for carrying the cushion in spaced relation above the baseand being secured thereto, the support carrying:

(i) a cam assembly disposed proximate the center thereof and having avertical axis of symmetry, the cam assembly carrying opposed peripheralcircular (convex) portions on either side of the axis of the symmetry,each opposed peripheral circular portion rotatable about its centre, andanother portion adjacent each circular portion (for example, recesses,indentations, indented portions), the outer surfaces of which otherportions being closer to one another than the circular (convex)portions;

(ii) means to permit the rotation of at least one circular cam portionat a time;

(iii) a pair of pawls on either side of the cam assembly, each pawlbeing secured for pivotal movement and having its end closest the camassembly carrying a recess corresponding in shape to the circular camportion for normally being engaged therewith whereby rotation of atleast one of the circular portions about its center (as for example bypivoting of one part of the cam assembly carrying the circular portionto be displaced or rotation of the cam assembly or a portion thereof)permits the end of the pawl carrying the recess to follow the outersurface of the cam assembly from the circular portion to the portionadjacent each circular portion, thereby releasing the associated pawlpermitting the seat to be adjusted and means are provided to cause thepawls to follow the outer surface configuration of the cam assembly andmeans are also provided to return the cam assembly and pawls to theirnormal position.

The pawls may be in turn pivotable removably secured at their other endsto ratchets, one of which is released when one of the pawls is releasedthereby permitting adjustment of the height and inclination of the seat.

According to another aspect of the invention, a seat adjustment assemblyis provided for adjusting the inclination and vertical position of aseat cushion of a seat, the seat assembly comprising a pair of pawlsnormally releasably fixed against pivoting by their engagement with anassembly between them and which pawls when released one at a time,permit adjustment of the inclination and vertical position of the seatcushion, the assembly between the pawls comprising a cam assemblycarrying opposed peripheral circular (convex) portions each opposedperipheral circular portion rotatable about the centre of such circularportion and another portion adjacent each circular portion the outersurfaces of which being closer to one another than the circular portionsare close to one another (for example recesses, indented portions,indentations) and the ends of the pawls engaging the assembly carry acircular recess corresponding in shape to the circular cam portion forwhich they are engaged and whereby means are provided for displacing thecam assembly and thus the pawls to permit adjustment and means areprovided for returning the cam assembly and pawls to their normalposition. Preferably the cam assembly carries a vertical axis ofsymmetry therethrough with one of the circular cam portions and one ofthe other portions of the cam on either side of the axis of symmetry.

According to another aspect of the invention a seat adjustment assemblyis provided for adjusting the inclination and vertical position of aseat cushion of a seat above the base of the seat, the seat assemblycomprising:

(a) a base;

(b) a seat cushion supported in spaced relation above the base:

(c) a support for carrying the cushion in spaced relation above the baseand being secured thereto, the support carrying:

(i) a cam assembly proximate the center thereof and carrying opposedperipheral circular portions each opposed peripheral circular portionrotatable about the centre thereof and another portion adjacent eachcircular portion the outer surface of each portion being closer to oneanother than the circular portions are close to one another;

(ii) means to cause the rotation of at least one circular cam portion ata time;

(iii) means to limit the rotation of the at least one circular camposition;

(iv) a pair of pawls, one on either side of the cam assembly pivotallysecured intermediate their ends to the support to pivot with respect tothe support, each pawl carrying a circular recess on the end thereofclosest the cam assembly in the form of a cam follower corresponding inshape to the circular cam portion to which it is adjacent for engagingsuch circular portion of the cam assembly, the other end of each pawlcarrying at least one fastener (securing) element for removably securingeach pawl to a component (in one embodiment, a ratchet) for permittingraising and/or lowering the front and/or rear of the seat cushion:

(v) means to cause each pawl to pivot when the pawl surface proximatethe pawl recess engages the outer surface of the other portion proximatethe circular cam portion to permit adjustment of the seat cushion andmeans to ensure restoration of the securing of the component and pawlafter adjustment of the seat cushion and the cam assembly to itsoriginal position.

In one embodiment, each fastener element of each pawl may be removablysecurable to a complementary fastener element of a ratchet forpermitting raising and/or lowering the front and/or rear of the seatcushion.

According to another aspect of the invention the other portion adjacenteach circular portion may be above the circular portion.

According to another aspect of the invention, the other portion adjacenteach circular portion may be below the circular portion. Where eachother portion is above each circular portion, the means to cause eachpawl to pivot when the pawl surface proximate the pawl recess engagesthe outer surface of the other portion proximate the circular camportion comprises spring means for urging the end of each pawl proximatethe cam downwardly when the pawl engaged the other portion above the camand the means to ensure restoration of the securing of the component andpawl after adjustment of the seat cushion and the cam assembly to itsoriginal position preferably comprises the same spring means. Preferablythe spring means is secured to a rotatable lever which is secured to thecam for rotating the cam. When the lever was released, the spring meansreturns the lever to its original position.

According to one aspect of the invention, a seat adjustment assembly isprovided for adjusting the inclination and vertical position of a seatcushion of a seat above the base of the seat, the seat assemblycomprising:

(a) a base;

(b) a seat cushion support in spaced relation above the base;

(c) pair of elongated members for carrying the cushion in spacedrelation above the base and being secured thereto, each elongated memberbeing carried proximate one side edge of the seat cushion on theunderside thereof, and carrying:

(i) a cam proximate the center thereof rotatable about an axis extendingperpendicular to the plane of the cam, the axis being carried in a rodjoining each cam and being rotatable with respect to each elongatedmember, each cam carrying diametrically opposed peripheral circularportions on either side of the axis and another portion above eachcircular portion the outer surface of which being closer through itsentire length to the axis than the circular portion the peripheralcircular portions being rotatable about their centre coinciding with theaxis in the rod;

(ii) means to rotate the rod (for example a lever);

(iii) a pair of pawls, one on either side of the cam pivotally securedintermediate their ends to the elongated member to pivot with respect tothe cam, each pawl carrying a circular recess on the end thereof closestthe cam in the form of a cam follower corresponding in shape to thecircular portion of the cam for engaging the circular portion of thecam, the other end of each pawl carrying at least one fastener element;

(iv) a ratchet being pivotally secured to the elongated member andcarrying a complementary fastener element for removably securing thepawl to the ratchet, (preferably the fastener and complementary fastenerelements being a tooth and receiving notches);

(v) means to cause each pawl proximate the cam to pivot downwardly whenthe pawl recess engages the other cam surface portion above the circularcam surface portion (preferably in the form of a torsion spring); and

(vi) means to urge the end of the ratchet bearing the complementaryfastener element to rotate about the pivot point of the ratchet withrespect to the elongate member (preferably in the form of a spring)whereby when the recess of the pawls carrying the cam follower surfaceengages the upper portion of the cam closer the axis, the fastenerelement is disengaged from the complementary element on the ratchet,permitting the ratchet to pivot.

(d) each ratchet also being pivotably secured to the base and carryingan arcuate slot spaced from the pivot of each ratchet to the elongatedmember and each elongated member carrying a pin for riding in eacharcuate slot whereby when the ratchet is permitted to pivot with respectto the elongated member, it also pivots with respect to the base thuscausing the pin carried in each slot to move in the slot foraccommodating the adjustment of the seat and whereby only one of thepawls on each elongated member is permitted to rotate upwardly at anyone time for adjustment of the front or rear of the seat cushion at anyone time.

According to another aspect of the invention, the axis of the cam andthus the cam are rotated by rotation of a lever either counterclockwiseor clockwise in a vertical plane or zone. Preferably the rotation of thelever upwardly permits adjustment of the front of the seat cushion andthe lowering of the lever permits adjustment of the rear of the seatcushion.

Preferably the ratchets opposite one another on the elongated membersare secured to one another as for example by a bar. Preferably the meansto urge the end of the ratchet bearing the complementary fastenerelements to rotate comprises a compression spring secured at each end toeach of the ratchets secured to the same elongate member so that wheneach of the ratchets is released one at a time, it is permitted torotate about the pivot points with respect to the elongate member andbase upwardly forcing the seat cushion upwardly. For lowering the seatcushion greater weight may be applied to the portion of the seat cushionabove the ratchet which has been permitted to pivot upwardly forcing itdownwardly and thus the seat portion which is then locked in positionwhen the cam is returned to its initial position.

Where each other portion is below each circular portion, the means tocause each pawl to pivot when the pawl recess engages the other portionproximate the circular cam portion comprises spring means for urging theends of each pawl proximate the cam downwardly as such end engaged theother portion and the means to ensure restoration of the securing of thecomponent and pawl of the seat cushion comprise a pair of L-shapedmembers each member pivotal with respect to the bottom of the cam at oneend for engaging teeth carried by the bottom of the cam and at other endfor engaging the underside of the pawl, each arm of the L-shaped membersbeing of substantially the same length and the member being pivotallysecured at the junction to the two arms to the support whereby when thecam is rotated and one of the apwls pivoted downwardly, the arm of themember secured to the cam is pivoted to lower the arm below the pawlthereby permitting the pawl to move downwardly and whereby after theseat cushion had been adjusted and the spring means released restoringthe cam, the member is pivoted to its original position with the arm ofthe L-shaped member below the pawl, pushes the pawl upwardly restoringit and the spring means to its original position.

According to another aspect of the invention, the cam assembly comprisestwo individual components with the circular portions being on separateparts independently movable from the other. In one embodiment each partis operated by a lever by pushing the separate part when rotated in onedirection and which separate parts are secured together by spacing meansso when one of the separate parts is rotated and released the seapratepart is urged by the spring to rotate towards its original position.

According to another aspect of the invention, a lever assembly isprovided for six-way seat adjustment of the position of a seat carriedon a base,

(a) forwards and backwards along a track or rail from one position toanother position;

(b) raising or lowering the front of the seat relative to the rear ofthe seat; and

(c) raising or lowering the rear of the seat relative to the front ofthe seat, the lever being pivotally secured in a holder carried by theseat to pivot with respect to (preferably towards) the side of the seatthereby cause the removal of removably securable securing means normallycarried by the base securing the base of the seat to the track or railto be removed releasing the base of the seat permitting slideablemovement of the base on the track or rail and permit it to be secured atanother position along the track when the lever is released urging thesecuring means to secure the base of the seat to the track, the leveralso being rotatable in a vertical direction (without releasing the basefor movement on the track or rail) either clockwise or counterclockwiseto permit activation of a system for permitting vertical adjustment ofthe seat cushion. Preferably only one adjustment may be made at one time(either seat cushion inclination or longitudinal position). In oneembodiment the lever assembly operates with the adjustable seat assemblyfor adjusting the inclination and position of a seat cushion above thebase of the seat as previously described.

The invention will now be illustrated with reference to the followingdrawings and detailed description of the structural embodimentsdisclosed in the drawings.

BRIEF DESCRIPTION OF THE DRAWINGS

FIGS. 1, 2 and 3 are side views of an automobile seat constructedaccording to an embodiment of the invention illustrating thelongitudinal adjustability of the seat (FIG. 1), the upward verticaladjustment of the front of the seat with respect to the rear of the seat(FIG. 2) and the upward vertical adjustment of the rear of the seat withrespect to the front of the seat (FIG. 3).

FIG. 4 is a perspective view of the seat adjustment assembly used toadjust the automobile seat shown in FIGS. 1, 2 and 3.

FIG. 5 is a close-up perspective view of part of the assembly shown inFIG. 4.

FIG. 6 is a perspective view of part of the structure shown in FIGS. 4and 5.

FIG. 7 is a schematic side view of part of the assembly shown in FIGS. 4and 5.

FIG. 8 is a top view of part of the structure shown in FIGS. 4 and 5.

FIG. 9 is a schematic side view of the assembly shown in FIGS. 4 and 5.

FIG. 10 is a cross-sectional view taken along the line 10--10 of FIG. 9looking in the direction of the arrows.

FIGS. 11 and 12 illustrate the operation of part of the assembly shownin FIGS. 4, 5 and 10 for the adjustment of the front and rear of theseat cushion of the seat.

FIG. 13 is a side view of part of another seat adjustment assembly whichmay be used for adjusting a seat.

FIG. 14 is a side view of still yet another seat adjustment assemblycapable of use to adjust the automobile seat shown in FIGS. 1, 2 and 3.

FIGS. 15 and 16 are close-up views of part of the assembly shown in FIG.14 in various relative operational positions.

FIGS. 17, 18 and 19 are perspective, top and side views respectively ofpart of another assembly according to another embodiment of theinvention.

FIG. 20 is a side view of part of another seat adjustment assembly whichmay be used for adjusting a seat.

FIG. 21 is a perspective view of the seat adjustment assembly shown inFIG. 20.

FIG. 22 is an exploded view of part of the structure shown in FIGS. 20and 21.

FIG. 23 is a perspective view of part of the seat adjustment assembly ofFIG. 20, 21 and 22 looking from another direction.

FIG. 24 is a top plan view of the seat adjustment assembly shown inFIGS. 20 to 23 inclusive.

FIG. 25 illustrates the operation of part of the seat adjustmentassembly of FIGS. 20 to 24 inclusive.

FIG. 26 is a close-up view of part of the structure shown in FIG. 25.

FIGS. 27 and 28 illustrate the operation of the assembly shwon in FIG.25.

DETAILED DESCRIPTION OF THE DRAWINGS

With reference to FIGS. 1, 2 and 3, there is shown seat 20 having seatcushion 22 and seat back 24 pivotally secured to pivot with respect toseat cushion 22. Seat cushion 22 is secured to seat adjustment assembly26. With reference to FIG. 4, seat adjustment assembly 26 is carried ontwo frame asesmblies 28, one on either side of seat cushion 22. Oneassembly 28, labelled as 30 is removably secured to one of the spacedstationary tracks 32 (see FIG. 6) closest lever 34 (see FIGS. 4 and 5)for sliding movement therealong when released by the removal of tooth 36(see FIG. 6) caused by the pivoting of arm 38 of latch 40 pivotallysecured to base 30 by pin 42 against the action of spring 44 whichnormally urges tooth 36 of latch 40 into a notch 44 of track 32.

Seat assembly 26 is carried on the two frame assemblies 28 on eitherside of and under seat cushion 22. Each frame assembly 28 includingassembly 26 comprises a generally L-shaped elongated sheet metal member46 (see FIGS. 4, 5 and 9) comprising a top flange 47 and down turnedwall 49 made up of end portions 46A and 46B at either end, verticallythinner portion 46A¹ and 46B¹ beside portions 46A and 46B, broaderportions 46A¹¹ and 46B¹¹ beside portions 46A¹ and 46B¹ respectively andcentral portion 48 of about the same width as portions 46A and 46B.Directly below reduced portion 46A¹ and 46B¹ and defined on either sideby sloping walls 50 and 52 of portions 46A and 46A¹ respectively andsloping walls 54 and 56 of portions 46B and 46B¹ respectively (see FIGS.9, 11 and 120 are recesses 58 and 60 respectively. Central portion 48carries an aperture 62 therethrough (see FIG. 8) for recieving one endof rod 64 and permitting rotation of rod 64 relative to member 46 ineach aperture 62. Proximate each end of rod 64 extending throughaperture 62, rod 64 supports a cam 66 on the side of wall 49 facing theother wall 49 and having a center 68 (see FIG. 9) on the longitudinalaxis 69 of rod 64. Cam 66 rotates with rod 64. With reference to FIG. 9,each cam carries on its outer peripheral surface, opposed circularportions 70 and 72 on either side of center 68 and other portions 74 and76 above circular portions 70 and 72. Each of portions 74 and 76 iscloser through its entire length to the centre 68 and thus axis 69 thancircular portions 70 and 72. Pawls 78 and 80 are pivotally secured towall 49 by pins 82 and 84 respectively secured to wall 49 of member 46.Each pawl 78 and 80 carries a recess 86 on one end of each pawl 78 and80 in the form of a cam follower corresponding in shape to the circularportions 70 and 72 of cam 66. Torsion spring 88 is wound around rod 64proximate each cam 66 and has its two arms 90 and 92 overlying each ofpawls 78 and 80, respectively proximate recesses 86 for urging each pawldownwardly. When each cam 66 is in the position shown in FIG. 9, eachpawl cannot be rotated by arms 90 and 92. However, when cam 66 is ineither of the positions shown in FIGS. 11 or 12 where only one of thecircular portions 70 and 72 remains engaged with one of the pawls 78 or80 at a time, the other pawl is free to rotate by the action of springarm 90 (see FIG. 11) or 92 (see FIG. 12).

On the other end of each of pawls 78 and 80 are teeth 94 spaced bynotches 96 for engagement with notches 98 (by teeth 94) and teeth 100(in notches 96) in ratchets 102 and 104 pivotally secured to wall 49 ofmember 46 by pins 106 and 108 respectively secured to wall 49. Ratchets102 and 104 carry slots 110 and 112 (which form portions of an annulus)for receiving pins 114 and 116 respectively fixed to wall 49 forlimiting the rotation of ratchets 102 and 103. On the end of eachratchet 102 and 104 remote the teeth 100 and notches 98, each ratchet102 and 104 is secured to either pin 118 and 120 as the case may be tobe pivotally secured thereto. Pin 118 and 120 do not pass through anopening in member 46 but rather lie below portion 46A¹ and generally inthe space between surfaces 50 and 52 (see FIG. 11) or portion 46B¹ andgenerally in the space between surfaces 54 and 56 (see FIG. 12)respectively at all times.

Ratchets 104 and 106 each carry L-shaped member 122 joined to theopposite rachet 104 and 106 on the opposite frame assembly 28. L-shapedmembers 122 connecting ratchets 104 and ratchets 106 on both frameassemblies 28 are secured together by a pair of normally stretchedsprings 124 (see FIGS. 4, 5, 8 and 9) to cause the L-shaped members torotate towards the other L-shaped member when one of the ratchets 102and 104 is released from engagement with one of pawls 78 and 80respectively which has been permitted to rotate releasing one ofratchets 102 or 104 by one of arms 90 or 92.

Pins 118 and 120 are in turn after passing through ratchets 102 and 104respectively on opposing frame assemblies 28, secured to supports 130and 132 carried on each base 30. Support 132 comprises a pair of walls132A and 132B carrying aligned holes 134 for securing pin 120 to base30. Support 130 comprises a pair of walls 130A and 130B carrying alignedelongated slots 13 for securing rod 118 to base 30.

With reference to FIGS. 4, 5, 7 and 8, one elongated member 46 has beenmodified to provide elongated slot 140 through top flange 47. Rod 64passing through aperture 62 carries pin 142 securing arm 144 rotatableon pin 142. Therefore, as arm 144 rotates, pin 142 and thus rod 64carrying cams 66 are rotated. Arm 144 carries on the end thereof remotepin 142, pin 146 for securing in elongated slot 148 in arm 150 so thatas arm 150 is rotated clockwise, arm 144 is rotated counterclockwise andvice versa. Arm 150 is secured by pin 152 (see Figure 8) passing throughwall 49 and arm 150 to sleeve 154 secured over pin 152. Sleeve 154comprises two sections 154A (top section) and 154B (bottom section)spaced from each other carrying laterally extending flanges 156 and 158,flange 156 connected to top section 154A and flange 158 connected tobottom section 154B. Torsion spring 160 is wound around sleeve 154 andhas its ends 160A and 160B positioned above and below projection 162carried by top flange 47 to extend between ends 160A and 160B so thatwhen sleeve 154 is forced to rotate clockwise or counterclockwiseagainst the action of spring 160, spring 160 is wound so that whensleeve 154 is free to rotate, it is returned to its initial positionshown in FIGS. 4, 5, and 8. Lever 164 is secured to sleeve 154 andcomprises elongated tubular member 166 covered by cap 168 at one end andflattened at the other end at 170 to be carried between flanges 156 and158 to be secured thereto by pin 172 (see FIG. 7) passing throughapertures 156A in flange 156, 170A in flattened portion 170 and 158A inflange 158. When lever 164 is lifted by pulling upwardly on tubularportion 166 proximate cap 168, arms 156 and 158 are lifted (see FIG. 2)rotating sleeve 154 (against the action of spring 60) and arm 150counterclockwise and thus arm 144 clockwise. When lever 164 is releasedit falls to its normal position shown in FIG. 1 by the action of arm160B of spring 160 on flange 162. Similarily when lever 164 is depressedby pushing down on tubular portion 166 proximate cap 168, arms 156 and158 are depressed (see FIG. 3) rotating sleeve 154 (against the actionof spring 160) and arm 150 and thus arm 144 counterclockwise. When lever164 is released it is raised to its normal position shown in FIG. 1 bythe action of arm 160A of spring 160 on flange 162.

Arm 166 is secured with flattened portion 170 extending between arms 156and 158 between sections 154A and 154B extending through slot 174 (seeFIG. 7) welded to upstanding plate 176 oriented to extend at 90 degreesto the plane of flattened portion 170. Lever 161 is pivotable on pin 172laterally away from and towards frame assembly 28 between arms 156 and158. Plate 176 is positioned between arm 38 and base 30 to engage edge38A of arm 38. Therefore, as lever 164 is pushed inwardly, plate 176 ispivoted outwardly engaging edge 38A of arm 38 causing latch 40 to pivoton pin 42 stretching spring 44A and removing tooth 36 from notch 44,permitting base (and thus seat 20) to move freely on track (rail) 32 toanother position.

Thereafter, lever 164 is released causing latch 40 to pivot by therestoration of spring 44A to its normal unstretched condition movingtooth 36 into another notch 44. To prevent base 30 and rail 32 fromseparating, a rolling spring 180 (see FIG. 10) is carried in a carriage182 to roll in the space between track or rail 32 and base 30 andstopped by bumps (one of which is shown at 184) suitably placed on theinterior surfaces of rail 32 and base 32 to stop spring 180 preventingthe base from sliding further along track 32.

To raise the seat cushion 22 relative to base 30 and raise or lower thefront of the seat cushion 22 relative to the rear or raise or lower therear of the seat cushion 22 relative to the front, lever 164 is pickedup or lowered as the case may be. To raise the height of the front seatcushion 22, lever 164 is lifted and held (see FIG. 2) rotating arm 150clockwise and thus arm 144 clockwise rotating rod 64 and each cam 66clockwise causing each cam to move circular portion 70 away from recess86 and move portion 74 into recess 86 permitting the end of pawl 78proximate recess 86 to pivot downwardly by arm 91 of spring 88 torelease teeth 94 from notches 98 and teeth 100 from notches 96 as pawl78 is pivoted on pin 82. Because recess 86 of pawl 80 remains engagedwith circular portion 72, pawl 80 is not released. As pawl 78 pivots,ratchet 102 is free to rotate about pin 106 and rod 118 by the action ofspring 124. When this happens if the person sitting on the seat isleaning back in the seat (with the person's weight towards the rear ofthe seat) the front of member 46 (because it is secured to ratchet 102)rises (see FIGS. 11 and 14). Springs (not shown) exert an upward forceon seat cushion constantly urging it upwardly to counter the user'sweight who is adjusting the seat. When the front of the seat ispermitted to rise to the desired height, the user releases the leverreturning the cam 66 to its original position locking recess 86 tocircular portion 70 locking the teeth 94, 100 and notches 96, 98 of thepawl 78 and ratchet 102 together fixing the height of the front of theseat.

If the front seat is to be lowered, after lever 64 is raised the usermerely sits on the front part of the seat, causing the front of the seatto be pushed down to the desired height. Lever 164 is then released.Rotation of ratchet 102 is limited by pin 114 riding in slot 110. As isapparent a portion of the surface of each cam 66 and a portion of camfollower surface of recess 86 are always engaged to ensure the integrityof the structure is maintained. As is also apparent, the adjustment tothe seat is weight-operated by moving the weight of the user todifferent parts of the seat and only either the front or rear of thecushion is adjustable at one time. Where the leading end 46A ofelongated member 46 rises (as ratchet 102 pivots upwardly) elongatedslot 136 accommodates the movement of pin 118.

Where the rear of the seat cushion is to be raised the user of the seatmoves his/her weight toward the front of the seat taking most of his/herweight off the rear part of the seat. Lever 164 is then depressed andheld (see FIG. 3) rotating cam 66 counterclockwise thus moving portion76 of cam 66 to engage recess 86 (see FIG. 12) permitting pawl 80 to bedepressed by arm 92 proximate recess 86 and be rotated around pin 84releasing ratchet 104 to pivot about pin 108 and 120 under the action ofspring 124 raising the end of ratchet 104 carrying teeth 100 and notches98 thus lifting end 46B supporting seat cushion 22 as shown in FIG. 3,raising cushion 22. Lever 164 is then released. To lower the rear ofcushion 22, the person sits with his/her weight toward the rear ofcushion 22 as lever 164 is depressed pushing the seat down against theaction of the springs 124 compressing springs 124.

As previously described for longitudinal adjustment of seat 20 relativeto tracks 32, lever 164 is pivoted on pin 172 towards the one frameassembly 28 to which it is nearest causing plate 176 to engage edge 38Aof arm 38 and rotate latch 40 about pin 42 stretching spring 44Aremoving tooth 36 from notch 44. Thereafter, bases 30 on both sides ofseat 20 are able to slide on track (rails) 32 to a new position. Theuser thereupon releases lever 164 thereby permitting spring 44A to pulltooth 36 into a new notch 44 in (track) rail 32 causing the rotation oflatch 40 counterclockwise and thus arm 38 about pin 42 pushing plateinwardly, rotating lever 164 outwardly around pin 172 to its normalposition (see FIG. 5).

As is apparent, adjustment of the seat position and height is relativelysimple. For longitudinal adjustment, lever 164 is pushed inwardly andheld and the driver slides the seat on track (rail) 32 until the desiredposition is reached. Thereafter, lever 164 is released locking the seatin position. As is apparent, lever 164 is held inwardly until theadjustment is completed. For adjusting the height and inclination ofcushion 22, lever 164 is either depressed or lifted and the person'sweight shifted to cause the front or rear of the cushion to be depressedor be raised under spring action as the case may be.

The seat assembly is of a lower profile (being about 62 mm in height)enhancing its stability. Additionally, because of the type of relativemovement of the various components, noise is minimized during operation.

With reference to FIG. 13 cam arrangement 200 is provided which may besubstituted for cam 66, rod 64 and torsion spring 88 shown in FIG. 9.

Cam arrangement 200 comprises cam section 266¹ and 266¹¹ pivoted torotate on pin 268¹ and 268¹¹ respectively secured to portion 48 ofassembly 46. Cam sections 266¹ carries circular portion 270 and cam266¹¹ carries circular portion 272 opposite circular portion 270.Portions 274 and 276 are positioned above circular portions 270 and 272respectively. Flanges 202 and 204 are connected to each cam 266¹ and266¹¹ respectively and are connected by spring 206 connected by ends206¹ and 206¹¹ to flanges 202 and 204 respectively.

Disposed between cam sections 266¹ and 266¹¹ is lever 208 pivotallysecured at its bottom 208b by pin 210 to portion 48 of member 46 andcarrying handle 212. Pivoted on pin 210 behind lever 208 are drivemembers 214¹ and 214¹¹ carrying a contact surface 216¹ and 216¹¹ in thesame plane as lever 208. Driven members 214¹ and 214¹¹ carry pins 218¹and 218¹¹ respectively secured to members 214¹ and 214¹¹ respectivelyfor engaging side edges 267¹ and 267¹¹ respectively on one side of drivemember 214¹ and 213¹¹ respectively and for being secured to extend intoarcuate slots 220¹ and 220¹¹ respectively through portion 48 of member46 which arcuate slots 220¹ and 220¹¹ define the extent of movement ofpins 218¹ and 218¹¹. Pawl 78 engages curved portion 270 of cam section266¹. Pawl 80 engages curved portion 272 of cam section 266¹¹.

In the operation of arrangement 200, when lever 208 is pushed to oneside or the other, either pin 218¹¹ or pin 218¹ is pushed to one side toengage one surface 267¹ or 267¹¹ respectively in its slot 220¹ or 220¹¹thereby rotating either cam section 266¹ or 266¹¹ causing either pawl 78or 80 to rotate stretching spring 206 in the manner previouslydescribed. When lever 208 is released, spring 206 restores causing therotated cam section to pivot on its pivot to its initial positioncausing the released pawl to be restored postion. Thereafter the leveris pushed to the other side for adjustment purposes.

With reference to FIGS. 14, 15 and 16, cam arrangement 300 is disclosedfor substitution with cam 66 in FIG. 9 for securing to rod 68¹ aroundwhich rod 68¹ is secured torsion spring 88¹ and extending over pawls 78and 80 shown in FIG. 9. Cam arrangement 300 comprises cam 366 carryingopposed circular portions 370 and 372 on either side of rod 68¹ andother portions 374 and 376 below circular portions 370 and 372respectively. Each of portions 370 and 372 is closer through its entirelength to the center 68¹ and thus axis 69¹ than circular portions 370and 372.

Cam 366 also carries spaced teeth 302 (spaced by recesses 303) on thebottom circular periphery between portions 374 and 376. Teeth 302 andrecesses 303 are adopted to mesh with teeth 304¹ and 304¹¹ and recesses305¹ and 305¹¹ carried on the ends of elbows 306¹ and 306¹¹respectively. Elbows 306¹ and 306¹¹ are pivoted on pins 308¹ and 308¹¹respectively, secured to member 46. At the other end of each of elbows306¹ and 306¹¹ are arms 310¹ and 310¹¹ respectively. The distancebetween pivot pin 308¹ to the end of arm 310¹ is equal to the distancebetween pivot pin 308¹ to the outer extent of teeth 304¹ which arespread circularly on the end of elbow 306¹. The distance between pivotpin 308¹ to the end of arm 310¹¹ is equal to the distance between pivotpin 308¹¹ to the outer extent of teeth 304¹¹ which teeth are spreadcircularly on the end of elbow 306¹¹. Arms 310¹ and 310¹¹ normallyengage the arcuately curved undersurfaces 378¹ and 380¹ of pawls 78 and80 respectively when cam 366 in the position shown in FIG. 14. Torelease one of pawls 78 and 80 for seat adjustment purposes previouslydescribed from the position shown in FIGS. 14 and 15, cam 366 is rotatedon rod 68¹ bringing either the end of pawl 78 into the recess 374 or theend of pawl 80 into recess 376 respectively, permitting releasing of theratchet to which the pawl is secured (as previously discussed), eitherthe front or rear end of the seat cushion may be adjusted. Withreference to FIG. 16, cam 366 has been rotated clockwise about pivot pin68¹ rotating elbow 306¹ counterclockwise about pivot pin 308¹ until theposition shown in FIG. 16 and arm 306¹ counterclockwise to the positionshown. At the same time pawl 80 has entered recess 376 by the action oftorsion spring 88, raising the other end of the pawl from the associatedratchet permitting the seat cushion above the released ratchet to beadjusted. The engaging of the other pawl 78 engages portion 369 whichacts as a stop. When cam 366 is to be returned to its initial positionthe released and depressed pivot pawl must be elevated out of the recessinto which spring 88 has forced it. In this regard, as cam is rotatedcounterclockwise both elbows 306¹ and 306¹¹ are rotated clockwisecausing arm 310¹ to follow the undersurface 378¹ or pawl 78 and arm310¹¹ to rotate against the undersurface 380¹ of pawl 80 forcing thepawl to pivot upwardly about its pivot 84¹ forcing the spring arm ofspring 88 to rise, returning the arrangement to the position shown inFIGS. 14 and 15.

With reference to FIGS. 17, 18 and 19, parts of another embodiment ofthe invention are shown which permits only one adjustment to be made ata time (either seat cushion inclination or longitudinal position).Unlike the assembly shown in FIGS. 5, 7 and 8, the rotation of lever 164laterally on pin 172 cause arm 38 to pivot latch 40 by the engagement ofarm 38 with plate 176, also causes lever 164 to be caught between tines400A and 400B of fork 402, fixed to elongated member 46 therebyprecluding vertical movement of lever 164 when the longitudinal positionof the seat it to be changed. (see FIG. 18). When lever 164 is returnedto its original position locking the seat into its new longitudinalposition, the vertical adjustment of the seat may be accomplished byraising and lowering of lever 164 rotating cam 66. When lever 164 islowered or raised because of the size of plate 176¹ (which is smallerthan plate 176), plate 176 is taken out of engagement with arm 38 sothat when lever 164 is raised or lowered, arm 38 cannot engage plate176¹. (See FIG. 19)

With reference to FIGS. 20 and 24 inclusive, there is shown seatgenerally shown as 520 having seat cushion 522 and seat back 524pivotally secured at 523 to pivot with respect to seat cushion 522. Seatcushion is secured to seat adjustment assembly generally shown at 526.With reference to FIGS. 23 and 524 seat adjustment assembly 526 iscarried on frame assembly 528 on one side of seat cushion 522 to whichseat cushion 522 is secured and is secured to another assembly 530 (seeFIG. 23) on the other side of seat cushion 522 to which seat cushion 522is also secured. Each assembly 528 and 530 is secured to one of thespaced stationary tracks 523 for sliding movement there along whenreleased for movement by the release of for example, a tooth secured ina notch in track 532 (not shown).

With reference to FIG. 23, a runner 533 is secured to rise on each track532. Each runner carries L-shaped support members 534 and 534¹ whichframe assembled 528 and 530 are secured respectively.

With reference to FIGS. 21 and 22, L-shaped support 534 carriesproximate the center round aperture 536 spaced from top edge 538. Aboveaperture 536 top edge carries recess 540 comprising sloped side walls542 and 544, sloped towards central area 546 from which upwardlyextending connected tab 548 extends. Tab 550 extends laterally outwardlyfrom the upper end of connector tab 548 away from L-shaped support 524.Stopped pin 552 passes through aperture 536 and is secured to lever arm554 on one side of upright flange 534A to pivot with lever arm 554 asarm 554 is raised or lowered when handle 556 is grasped and eitherpulled up or pushed down. Pin 552 carries on the other side of flange534A cam 566 to which it is secured and locked to rate therewith andtorsion spring 568 carrying upstanding arms 568A and 568B from the endsof spring 568. Cam 556 carries outwardly directed tab 567 which ispositioned directly below tab 550. Cam 556 has an axis of symmetry 569(see FIG. 20) and carries circular portions 570 and 572 on either sideof axis of symmetry 569. Wings 574 and 576 extend laterally from cam 566and carry stop surfaces 575 and 577 respectively. Between circularportions 570 and 572 is recess 578 defined on either end by sloped walls578A and 578B sloping towards the center of recess 578 from circularportions 570 and 572. Arms 568A and 568B of spring 568 are positioned onother side of overlying tabs 550 and 561 (see FIG. 21) Pawls 579 and 580are pivotally secured to support 534 by pins 582 and 584 passing throughapertures 579A and 579B and 580 and 580B in pawls 579 and 580 and rightflange 534A. Each of pins 582 and 584 carries a torsion spring 586 and588 respectively having arsm 586A and 586B and 588A and 588B at the endsthereof.

Pawls 579 and 580 carry cam follower surfaces 590 and 592 (curved tofollow surfaces 570 and 572 of cam 566) on L-shaped ends 590A and 592Acarrying inner surfces 590B and 592B. The other end of each of pawls 590and 592 carry two teeth 596 spaced by notch 598. Arm 586A of spring 586is secured to extend through aperture 600 in upright flange 534A (seeFIG. 21) and arm 586B wraps around pin 582¹. Arm 588A of spring 588 issecured to extend through aperture 602 in upright flange 534A and arm588B wraps under pawl 580.

Teeth 596 and notch 598 of each pawl are secured in a complementaryconfiguration of notches 598A and teeth 596A in ratchets 604 and 606.Each of ratchets 604 and 606 are pivotally secured to upright flange534A, ratchet 604 by rod 608 passing through aperture 609 upright flange534A and being secured on other side and ratchet 606 by rod 610 passingthrough aperture 611 (see FIG. 22) of upright flange 534A and beingsecured on the other side. Ratchet 604 carries an aperture 612A throughits end opposite the teeth 596A and notches 598A through which apertureplate 614 is pivotally secured through aperture 612B ratchet 604 by pin618 passing therethrough. Plate 614 also carries aperture 612C throughwhich pin 620 passes pivotally securing L-shaped member 620 to plate614. A similar L-shaped cushion support 620 is also pivotally secured bya pin 618 to ratchet 606.

Rod 608 carries torsion spring 622 and 624 of which wraps around pin 618(see FIG. 22) and the other end 626 of which wraps under pawl 579. Rod610 also carries a torsion spring 628, one end 630 sits under the upperlaterally extending flange 620A of flange 620 and the other end 632wraps around the end 534B of upright flange 534A.

Rods 608 and 610 are pivotally connected at their other ends throughplates 650 to L-shaped support 534¹. Plate 650 pivotally secured to rod608 is pivotally secured to another plate 652 by pin 658 in turnpivotally secured to an L-shaped cushion support 620. Plate 650pivotally secured to rod 610 is pivotally secured directly to anL-shaped cushion support 620. Rods 608 and 610 carry torsion springs 622and 628 respectively. Spring 622 has one end secured through an aperturein the upright flange of support 534¹ and the other end secured aboutpin 658 pivotally securing plate 650 to plate 652. Spring 624 has oneend carried under flange 654 at support 620 and the other end wrappedaround end 534¹¹ of support 534¹¹.

With reference to FIG. 20, each of supports 620 is secured to undersideof the seat cushion 522. Because each support 620 is pivotally securedto its associated plate, it is apparent this structure may be secure tosupport many different size cushions.

With reference to FIGS. 25 to 28 inclusive, the operation of seatadjustment assembly 526. When lever 554 is depressed (pushed down) cam566 is rotated clockwise causing both pawl 579 and 580 to ride on thecircular surfaces 570 and 572 respectively until portion 590A of pawl579 is forced by torsion spring 622 into recess 578 causing surface 590Bto engages surfaces 578A. While portion 590A continues to ride onportion 572 until it engages stop surface 577 of using 576. As portion590A enters recess 578 it is caused to continue to pivotcounterclockwise against surface 578A. The angles of surfaces 578A and590B are such so that only "point contact"(as opposed to line contact)exists between the two portions to ensure the two surfaces are notlocked together so that when cam 566 rotates counterclockwise surface578A forces surface 590B (and thus pawl 579) to pivot counterclockwisepushing portion 590A out of recess 578 to cause surface 590 to re-engagecircular portion 570.

When pawl 579 pivots counterclockwise, teeth 596 are removed fromnotches 598A permitting ratchets to rotate counterclockwise with rod608, permitting seat cushion 622 to rise at the rear end of the seat.Because the rear seat cushion portion proximate rod 608 is free to rise,it can be depressed under extra force (as by the passenger leaving backand concentrating his/her weight over rod 608, depressing the cushion,the desired height of the cushion can be set. At the same time, becausepawl 580 engages curved surface 572, the height of the front of cushion522 cannot be adjusted. (see FIG. 27).

By reversing the rotation of the cam (counterclockwise) by lifting arm554 by handle 556 (see FIG. 28) the front of the cushion can beadjusted.

As many changes can be made to the embodiments without departing fromthe scope of the invention, it is intended that all matter contained beinterpreted as illustrative of the invention and not in a limitingsense.

The embodiments of the invention in which an exclusive property orprivilege is claimed are as follows:
 1. A seat adjustment assembly foradjusting the inclination and vertical position of a seat cushion of aseat above the base of the seat, the seat assembly comprising:(a) abase; (b) a seat cushion supported in spaced relation above the base;(c) a support for carrying the cushion in spaced relation above the baseand being secured thereto, the support carrying:(i) a cam assemblydisposed proximate the centre thereof and carrying opposed peripheralcircular (convex) portions, each opposed peripheral circular portionrotatable about the centre of such circular portion and another portionadjacent each circular portion, the outer surfaces of which otherportions being closer to one another than the circular portions areclose to one another; (ii) means to permit the rotation of at least onecircular cam portion at a time; (iii) a pair of pawls on either side ofthe cam assembly each pawl being secured for pivotal movement and havingits end closest the cam assembly carrying a circular recesscorresponding in shape to the circular cam portion for normally beingengaged therewithwhereby rotation of at least one of the circularportions about its centre permits the end of the pawl carrying therecess to follow the outer surface of the cam assembly from the circularportion to the portion adjacent each circular portion, thereby releasingthe associated pawl permitting the seat to be adjusted and means areprovided to cause the pawls to follow the outer surface configuration ofthe cam assembly and means to return the cam assembly and pawls to theirnormal position.
 2. The seat adjustment assembly of claim 1, wherein thedisplacement of at least one of the circular portions of the camassembly is accomplished by pivoting of the one part of the cam assemblycarrying the circular portion to be displaced.
 3. The seat adjustmentassmbly of claim 1, wherein the displacement of at least one of thecircular portions of the cam assembly is accomplished by rotation of thecam assembly or a portion thereof.
 4. The seat adjustment assembly ofclaim 1, wherein the pawls are pivotally removably secured at theirother ends to ratchets, one of which is released when one of the pawlsis released, thereby permitting adjustment of the height of inclinationof the seat.
 5. A seat adjustment assembly for adjusting the inclinationand vertical position of a seat cushion of a seat above the base of aseat, the seat assembly comprising:(a) a base; (b) a seat cushionsupported in spaced relation above the base;(c) a support for carryingthe cushion in spaced relation above the base and being secured thereto,the support carrying: (i) a cam assembly disposed proximate the centrethereof and having a vertical axis of symmetry, the cam assemblycarrying opposed peripheral circular (convex) protions on either side ofthe axis of symmetry, each opposed peripheral circular portion rotatableabout its centre and another portion adjacent each circular portion, theouter surfaces of which being closer to one another than the circularportions; (ii) means to permit the rotation of at least one circular camportion at a time; (iii) a pair of pawls on either side of the camassembly, each pawl being secured for pivotal movement and having itsend closest the cam assembly carrying a circular recess corresponding inshape to the circular cam portion for normally being engagedtherewithwhereby rotation of at least one of the circular portions aboutits centre permits the end of the pawl carrying the recess to follow theouter surface of the cam assembly from the circular portion to theportion adjacent each circular portion, thereby releasing the associatedpawl permitting the seat to be adjusted and means are provided to causethe pawls to follow the outer surface configuration of the cam assemblyand emans are also provided to return the cam assembly and pawls totheir normal position.
 6. The seat assembly of claim 5, wherein thedisplacement of at least one of the circular portions of the camassembly is accomplished by pivoting of the one part of the cam assemblycarrying circular portion to be displaced.
 7. The seat assembly of claim5, wherein the displacement of at least one of the circular portions ofthe cam assembly is accomplished by rotation of the cam assembly or aportion thereof.
 8. The seat adjustment assembly of claim 5, wherein thepawls are pivotally removably secured at their other ends to ratchets,one of which is released when one of the pawls is released therebypermitting adjustment of the height and inclination of the seat.
 9. Aseat adjustment assembly for adjusting the inclination and verticalposition of a seat cushion of a seat, the seat assembly comprising apair of pawls normally releasably fixed against pivoting by theirengagement with an assembly disposed between them and which pawls whenreleased one at a time, permit adjustment of the inclination andvertical position of the seat cushion, the assembly between the pawlscomprising a cam assembly carrying opposed peripheral circular (convex)portions, each opposed peripheral circular portion rotatable about thecentre of such circular portion and another portion adjacent eachcircular portion the outer surfaces of which being closer to one anotherthan the circular portions are close to one another and the ends of thepawls engaging the assembly carrying a circular recess corresponding inshape to the circular cam portion to which they are engaged and wherebymeans are provided for displacing the cam assembly and thus the pawls topermit adjustment and means are provided for returning the cam assemblyand pawls to their normal position.
 10. The seat assembly of claim 9,wherein the cam assembly carries a vertical axis of symmetrytherethrough with one of the circular cam portions and one of the otherportions of the cam on either side of the axis of symmetry.
 11. a seatadjustment assembly for adjusting the inclination and vertical positionof a seat cushion of a seat above the base of the seat, the seatassembly comprising:(a) a base; (b) a seat cushion supported in spacedrelation above the base; (c) a support for carrying the cushion inspaced relation above the base and being secured thereto, the supportcarrying:(i) a cam assembly proximate the centre thereof and carryingopposed peripheral circular portions, each opposed peripheral circularportion rotatable about the centre thereof, and another portion adjacenteach circular portion the outer surfaces of each portion being closer toone another than the circular portions are close to one another; (ii)means to cause the rotation of at least one circular cam portion at atime; (iii) means to limit the rotation of the at least one circular camportion; (iv) a pair of pawls, one on either side of the cam assemblypivotally secured intermediate their ends to the support to pivot withrespect to the support, each pawl carrying a circular recess on the endthereof closest the cam assembly in the form of a cam followercorresponding in shape to the circular cam portion to which it isadjacent for engaging such circular portion of the cam, the other end ofeach pawl carrying at least one fastener (securing) element forremovably securing each pawl to a component for permitting raisingand/or lowering the front and/or rear of the seat cushion; (v) means tocause each pawl to pivot when the pawl surface proximate the pawl recessengages the outer surface of the other portion proximate the circularcam portion to permit adjustment of the seat cushion and means to ensurerestoration of the securing of the component and pawl after adjustmentof the seat cushion and the cam assembly to its original position. 12.The seat adjustment assembly of claim 11, wherein the component to whicheach pawl is removably secured by the at least one fastener (securing)element is a ratchet.
 13. The seat adjustment assembly of claim 12,wherein each fastener element of each pawl is removably securable to acomplementary fastener element of a ratchet for permitting raisingand/or lowering the front and/or rear of the seat cushion.
 14. The seatadjustment assembly of claim 13, wherein the other portion adjacent eachcircular portion is above the circular portion.
 15. The seat adjustmentof claim 14, wherein the means to cause each pawl to pivot when the pawlsurface proximate the pawl recess engages the outer surface of the otherportion proximate the circular cam portion comprises spring means forurging the end of each pawl proximate the cam downwardly when the pawlengages the other portion above the cam and the means to ensurerestoration of the securing of the cam and pawl after adjustment of theseat cushion and the cam assembly to its original position comprises thesame spring means.
 16. The seat adjustment assembly of claim 15, wherebywhen the lever was released, the spring means returns the lever to itsoriginal position.
 17. The seat adjustment assembly of claim 13, whereinthe other portion adjacent each circular portion is below the circularportion.
 18. The seat adjustment assembly of claim 12, wherein the otherportion adjacent each circular portion is above the circular portion.19. The seat adjustment assembly of claim 18, wherein the means to causeeach pawl to pivot when the pawl surface proximate the pawl recessengages the outer surface of the other portion proximate the circularcam portion comprises spring means for urging the end of each pawlproximate the cam downwardly when the pawl engages the other portionabove the cam and the means to ensure restoration of the securing of thecam and pawl after adjustment of the seat cushion and the cam assemblyto its original position comprises the same spring means.
 20. The seatadjustment assembly of claim 19, whereby when the lever was released,the spring means returns the lever to its original position.
 21. Theseat adjustment assembly of claim 12, wherein the other portion adjacenteach circular portion is below the circular portion.
 22. The seatadjustment assembly of claim 11, wherein each other portion is beloweach circular portion, the means to cause each pawl to pivot when thepawl recess engages the other portion proximate the circular cam portioncomprises spring means for urging the ends of each pawl proximate thecam downwardly as such end engaged the other portion and the means toensure restoration of the securing of component and pawl of the seatcushion comprises a pair of L-shaped members each member pivotal withrespect to the bottom of the cam at one end for engaging teeth carriedby the bottom of the cam and at the other end for engaging the undersideof the pawl each arm of the L-shaped members being of substantially thesame length and the member being pivotally secure at the junction to thetwo arms to the support, whereby when the cam is rotated an one of thepawls pivoted downwardly the arms of the member secured to the cam ispivoted to lower the arm below the pawl thereby permitting the pawl tomove downwardly, and whereby after the seat cushion had been adjustedand the spring means released restoring the cam, the member is pivotedto its original position with the arm of the L-shaped member below thepawl, pushed the pawl upwardly restoring it and the spring means to itsoriginal position.
 23. The seat adjustment assembly of claim 11, whereinthe cam assembly comprises two individual components with the circularportions being on separate parts independently moveable from the other.24. The seat adjustment assembly of claim 23, wherein each part isoperated by a lever pushing the separate part when rotated in onedirection and which separate parts are secured together by spring meansso when one of the separate parts is rotated and released, the separatepart is urged by the spring to rotate towards its original position. 25.A seat adjustment for adjusting the inclination and vertical position ofseat cushion of a seat above the base of the seat, the seat adjustmentassembly comprising:(a) a base; (b) a seat cushion supported in spacedrelation above the base; (c) a pair of elongated members for carryingthe cushion in spaced relation above the base and being secured thereto,each elongated member being carried proximate one side edge of the seatcushion on the underside thereof and carrying:(i) a cam proximate thecentre thereof rotatable about an axis extending perpendicular to theplane of the cam, the axis being carried in a rod joining each cam andbeing rotatable with respect to each elongated member, each cam carryingdiametrically opposed peripheral circular portions on either side of theaxis and another portion above each circular portion the outer surfaceof which being closer through its entire length to the axis than thecircular portion, the peripheral circular portions being rotatable abouttheir centre coinciding with the axis in the rod; (ii) means to rotatethe rod; (iii) a pair of pawls, one on either side of the cam pivotallysecured intermediate their ends to the elongated member to pivot withrespect to the cam, each pawl carrying a circular recess on the endthereof closest the cam in the form of a cam follower corresponding inshape to the circular portion of the cam for engaging the circularportion of the cam, the other end of each pawl carrying at least onefastener element; (iv) a ratchet being pivotally secured to theelongated member and carrying a plurality of complementary fastenerelements for removeably securing the pawl to the ratchet; (v) means tocause each pawl proximate the cam to pivot downwardly when the pawlrecess engages the other cam surface portion above the circular camsurface portion, and (vi) means to urge the end of the ratchet bearingthe complementary fastener element to rotate about the pivot point ofthe ratchet with respect to the elongated member whereby when the recessof the pawl carrying the cam follower engages the upper portion of thecam closer the axis, the fastener element is disengaged from thecomplementary element on the ratchet, permitting the ratchet to pivot;(d) each ratchet being pivotally secured to the base and carrying anarcuate slot spaced from the pivot point of each ratchet to theelongated member and each elongated member carrying a pin for riding ineach arcuate slot whereby when the ratchet is permitted to pivot withrespect to the elongated member, it also pivots with respect to the basethus causing the pin carried in each slot to move in the slot foraccommodating the adjustment of the seat and whereby only one of thepawls on each elongated member is permitted to rotate upwardly at anyone time for adjustment of the front or rear of the seat cushion at anyone time.
 26. The adjustable seat assembly of claim 25, wherein themeans to cause each pawl to pivot downwardly comprises a spring arm of atorsion spring wound around the rod engaging the top of the pawlproximate the cam constantly urging the portion of the pawl proximatethe cam to rotate downwardly.
 27. The adjustable seat asesmbly of claim26, wherein the axis of the cam and thus the cam, is rotated by rotationof a lever either counterclockwise or clockwise.
 28. The adjustable seatassembly of claim 27, wherein the rotation of the lever upwardly adjuststhe height of the front of the seat cushion and the rotation of thelever downwardly adjusts the height of the rear of the seat cushion. 29.The adjustable seat assembly of claim 28, further comprising acompression spring secured at each end to each of the ratchets on thesame elongated member so that when the ratchets are each released one ata time, they rotate about the pivot point with respect to both the baseand elongated member upwardly.
 30. The adjustable seat assembly of claim27, further comprising a compression spring secured at each end to eachof the ratchets on the same elongated member so that when the ratchetsare each released one at a time, they rotate about the pivot point withrespect to both the base and elongated member upwardly.
 31. Theadjustable seat assembly of claim 26, further comprising a compressionspring secured at each end to each of the ratchets on the same elongatedmember so that when the ratchets are each released one at a time, theyrotate about the pivot point with respect to both the base and elongatedmember upwardly.
 32. The adjustable seat assembly of claim 25, whereinthe axis of the cam and thus the cam, is rotated by rotation of a levereither counterclockwise or clockwise.
 33. The adjustable seat assemblyof claim 32, wherein the rotation of the lever upwardly adjusts theheight of the front of the seat cushion and the rotation of the leverdownwardly adjusts the height of the rear of the seat cushion.
 34. Theadjustable seat assembly of claim 33, further comprising a compressionspring secured at each end to each of the ratchets on the same elongatedmember so that when the ratchets are each released one at a time, theyrotate about the pivot point with respect to the both the base andelongated member upwardly.
 35. The adjustable seat assembly of claim 32,further comprising a compression spring secured at each end to each ofthe ratchets on the same elongated member so that when the ratchets areeach released one at a time, they rotate about the pivot point withrespect to both the base and elongated member upwardly.
 36. Theadjustable seat assembly of claim 25, further comprising a compressionspring secured at each end to each of the ratchets on the same elongatedmember so that when the ratchets are each released one at a time, theyrotate about the pivot point with respect to both the base and elongatedmember upwardly.